Synonyms and antonyms.Synonymy.Synonyms are the words of the same part of speech different in their sound-form but similar in their meaning and interchangeable at least in one context.There are very few perfect synonyms. They usually differ in some aspect of their meaning — according to tis they can be ideographic (differ in denotational component: referential and conceptual) and stylistic (connotational component: emotive charge and stylistic reference).Ideographic synonyms express the same concept but present it in slightly different ways (clever-intelligent-bright).Stylistic (to love -to adore; insane-mad).Some stylistic synonyms express dialectic difference (autumn-fall).The native word is usually more neutral. The borrowed — more official (work-labour — double-scaled pattern; to rise-to mount-to accent — triple-scaled pattern).

Antonymy (semantic opposition).Antonyms are words which express opposite or contrasting meanings.Antonyms are subdivided into:1. Gradable — represent the extremes of the quality. There are often adjectives that can be placed on the scale between them (hot-cold).2. Contradictory-complimentary — cannot exist without each other (dead-alive; leave-stay)3. Conversive — describe opposite attributes of the same situation (to buy-to sell — when one buys another sells)

THIS IS A DIFFICULT QUESTION TO ANSWER.I'M DEFINITELY SURE THAT HAPPINESS CAN'T MEAN THE SAME TO ALL THE PEOPLE.
IT IS SOMETHING THAT LIVES INSIDE EACH OF US.YOU SHOULD CAREFULLY THINK ABUOT THIS.
IT'S VERY SERIOUS